The Missouri River and Lake Sakakawea, its impoundment behind Garrison Dam, are North Dakota's link to the 33 CFR 83.03(n) Western Rivers definition; Devils Lake sits in a closed basin that does not drain to the Missouri, and is not claimed here as Western Rivers water. No Part 80 demarcation line exists in the state, so everything is inland water under 83.03(q). Whether a reservoir this far up the system carries the Western Rivers provisions is an OCMI determination and not something to infer from the river's name. Most North Dakota candidates are documenting service earned elsewhere; the record should name the water, the vessel and the route for each period, because REC St. Louis evaluates those and not the applicant's state.
33 CFR Part 80 draws no demarcation line in North Dakota. Its 106 sections cover the Atlantic, Gulf and Pacific coasts, Puerto Rico and the Virgin Islands, the Pacific islands and Alaska; a state with no coast has no section, which is itself the answer.
Western Rivers (the Missouri River) are defined at 33 CFR 83.03(n) and carry Inland Rules provisions the rest of inland water does not: 83.09(a)(ii), 83.14(d), 83.15(b) and the towing-light exception at 83.24(j).
This decides which rulebook you steer by, not where your credential may operate: the route limit is the 46 CFR Part 7 Boundary Line, and the two lines are not drawn in the same place. How the two lines differ · International Rules · Inland Rules
33 CFR Part 80 and the Part 83 definitions above read from eCFR on 12 Aug 2026. Any specific water is a determination for the cognizant Coast Guard Officer in Charge, Marine Inspection.